Limit boundary PU sizes in case of errors
In case of error clips, some PUs are marked as skip.
Ensure such PUs stay within the picture
Bug: 37615911
Test: ran POC included with the bug.
Change-Id: Ie0aeccc752cf556f9dea84de61c15a7906e1060b
(cherry picked from commit 62830d130b33ab196245e8fbda63639fe9420c18)